Portola Pharmaceuticals Announces Data Presentations Highlighting Syk/JAK Inhibitor Clinical Development Program at 52nd American Society of Hematology Annual Meeting

SOUTH SAN FRANCISCO, Calif., Dec. 4, 2010 /PRNewswire/ —
Portola Pharmaceuticals, Inc. today announced the presentation of
preclinical study results for its novel Syk and JAK inhibitor
program at the American Society of Hematology’s 52nd Annual Meeting
and Exposition. Portola’s novel Syk and JAK inhibitors are in
development to treat chronic inflammatory diseases, including
rheumatoid arthritis, and certain cancers, including non-Hodgkin’s
lymphoma and chronic lymphocytic leukemia.

Poster Presentation Details

Specific Inhibition of Syk Suppresses Leukocyte Immune Function
and Alleviates Inflammation In Rodent Models of Rheumatoid
Arthritis

Presenter: Greg Coffey, Ph.D., Portola
Pharmaceuticals
Poster Session: Lymphocytes, Lymphocyte Activation and
Immunodeficiency, Including HIV and Other Infections: Poster I
Date: Saturday, December 4, 5:30 – 7:30 p.m. ET
Location: Hall A3/A4 (Orange County Convention Center)
Poster Board I-707

P505-15, a Highly Selective SYK Inhibitor, Shows Significant
Activity in Primary CLL Cells and is Synergistic with Fludarabine
at Low Concentrations

Presenter: Stephen Spurgeon, M.D., Oregon Health &
Science University Knight Cancer Institute
Poster Session: Lymphoma – Pre-Clinical – Chemotherapy
and Biologic Agents: Poster I
Date: Sunday, December 5, 6:00 – 8:00 p.m. ET
Location: Hall A3/A4 (Orange County Convention
Center)
Poster Board II-719

Spleen Tyrosine Kinase (Syk) Inhibitors Block B Cell Receptor
Signaling and Survival In Chronic Lymphocytic Leukemia